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target="_self">requestAnimationFrame</a></li><li><a href="sampleTerrain.html" target="_self">sampleTerrain</a></li><li><a href="SceneMode.html" target="_self">SceneMode</a></li><li><a href="SceneTransforms.html" target="_self">SceneTransforms</a></li><li><a href="ScreenSpaceEventType.html" target="_self">ScreenSpaceEventType</a></li><li><a href="Shapes.html" target="_self">Shapes</a></li><li><a href="Simon1994PlanetaryPositions.html" target="_self">Simon1994PlanetaryPositions</a></li><li><a href="StencilFunction.html" target="_self">StencilFunction</a></li><li><a href="StencilOperation.html" target="_self">StencilOperation</a></li><li><a href="SvgPathBindingHandler.html" target="_self">SvgPathBindingHandler</a></li><li><a href="taskDispatcher.html" target="_self">taskDispatcher</a></li><li><a href="TextureMagnificationFilter.html" target="_self">TextureMagnificationFilter</a></li><li><a href="TextureMinificationFilter.html" target="_self">TextureMinificationFilter</a></li><li><a href="TextureWrap.html" target="_self">TextureWrap</a></li><li><a href="TimeConstants.html" target="_self">TimeConstants</a></li><li><a href="TimeStandard.html" target="_self">TimeStandard</a></li><li><a href="Tipsify.html" target="_self">Tipsify</a></li><li><a href="Transforms.html" target="_self">Transforms</a></li><li><a href="TridiagonalSystemSolver.html" target="_self">TridiagonalSystemSolver</a></li><li><a href="UniformDatatype.html" target="_self">UniformDatatype</a></li><li><a href="VertexLayout.html" target="_self">VertexLayout</a></li><li><a href="VerticalOrigin.html" target="_self">VerticalOrigin</a></li><li><a href="viewerDragDropMixin.html" target="_self">viewerDragDropMixin</a></li><li><a href="viewerDynamicObjectMixin.html" target="_self">viewerDynamicObjectMixin</a></li><li><a href="Visibility.html" target="_self">Visibility</a></li><li><a href="WindingOrder.html" target="_self">WindingOrder</a></li><li><a href="ComponentDatatype.html" target="_self">ComponentDatatype</a></li><li><a href="IndexDatatype.html" target="_self">IndexDatatype</a></li><li><a href="MaterialAppearance.MaterialSupport.html" target="_self">MaterialSupport</a></li></div><div id="glslItems"><li><a href="czm_antialias.html" target="_self">czm_antialias</a></li><li><a href="czm_columbusViewMorph.html" target="_self">czm_columbusViewMorph</a></li><li><a href="czm_computePosition.html" target="_self">czm_computePosition</a></li><li><a href="czm_currentFrustum.html" target="_self">czm_currentFrustum</a></li><li><a href="czm_eastNorthUpToEyeCoordinates.html" target="_self">czm_eastNorthUpToEyeCoordinates</a></li><li><a href="czm_ellipsoid.html" target="_self">czm_ellipsoid</a></li><li><a href="czm_ellipsoidContainsPoint.html" target="_self">czm_ellipsoidContainsPoint</a></li><li><a href="czm_ellipsoidNew.html" target="_self">czm_ellipsoidNew</a></li><li><a href="czm_ellipsoidWgs84TextureCoordinates.html" 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target="_self">czm_infinity</a></li><li><a href="czm_inverseModel.html" target="_self">czm_inverseModel</a></li><li><a href="czm_inverseModelView.html" target="_self">czm_inverseModelView</a></li><li><a href="czm_inverseModelView3D.html" target="_self">czm_inverseModelView3D</a></li><li><a href="czm_inverseNormal.html" target="_self">czm_inverseNormal</a></li><li><a href="czm_inverseNormal3D.html" target="_self">czm_inverseNormal3D</a></li><li><a href="czm_inverseProjection.html" target="_self">czm_inverseProjection</a></li><li><a href="czm_inverseView.html" target="_self">czm_inverseView</a></li><li><a href="czm_inverseView3D.html" target="_self">czm_inverseView3D</a></li><li><a href="czm_inverseViewRotation.html" target="_self">czm_inverseViewRotation</a></li><li><a href="czm_inverseViewRotation3D.html" target="_self">czm_inverseViewRotation3D</a></li><li><a href="czm_isEmpty.html" target="_self">czm_isEmpty</a></li><li><a href="czm_isFull.html" target="_self">czm_isFull</a></li><li><a href="czm_latitudeToWebMercatorFraction.html" target="_self">czm_latitudeToWebMercatorFraction</a></li><li><a href="czm_luminance.html" target="_self">czm_luminance</a></li><li><a href="czm_material.html" target="_self">czm_material</a></li><li><a href="czm_materialInput.html" target="_self">czm_materialInput</a></li><li><a href="czm_model.html" target="_self">czm_model</a></li><li><a href="czm_modelToWindowCoordinates.html" target="_self">czm_modelToWindowCoordinates</a></li><li><a href="czm_modelView.html" target="_self">czm_modelView</a></li><li><a href="czm_modelView3D.html" target="_self">czm_modelView3D</a></li><li><a href="czm_modelViewInfiniteProjection.html" target="_self">czm_modelViewInfiniteProjection</a></li><li><a href="czm_modelViewProjection.html" target="_self">czm_modelViewProjection</a></li><li><a href="czm_modelViewProjectionRelativeToEye.html" target="_self">czm_modelViewProjectionRelativeToEye</a></li><li><a href="czm_modelViewRelativeToEye.html" target="_self">czm_modelViewRelativeToEye</a></li><li><a href="czm_moonDirectionEC.html" target="_self">czm_moonDirectionEC</a></li><li><a href="czm_morphTime.html" target="_self">czm_morphTime</a></li><li><a href="czm_multiplyWithColorBalance.html" target="_self">czm_multiplyWithColorBalance</a></li><li><a href="czm_normal.html" target="_self">czm_normal</a></li><li><a href="czm_normal3D.html" target="_self">czm_normal3D</a></li><li><a href="czm_phong.html" target="_self">czm_phong</a></li><li><a href="czm_pixelSizeInMeters.html" target="_self">czm_pixelSizeInMeters</a></li><li><a href="czm_pointAlongRay.html" target="_self">czm_pointAlongRay</a></li><li><a href="czm_projection.html" target="_self">czm_projection</a></li><li><a href="czm_ray.html" target="_self">czm_ray</a></li><li><a href="czm_rayEllipsoidIntersectionInterval.html" target="_self">czm_rayEllipsoidIntersectionInterval</a></li><li><a href="czm_raySegment.html" target="_self">czm_raySegment</a></li><li><a href="czm_RGBToXYZ.html" target="_self">czm_RGBToXYZ</a></li><li><a href="czm_saturation.html" target="_self">czm_saturation</a></li><li><a href="czm_sceneMode.html" target="_self">czm_sceneMode</a></li><li><a href="czm_sceneMode2D.html" target="_self">czm_sceneMode2D</a></li><li><a href="czm_sceneMode3D.html" target="_self">czm_sceneMode3D</a></li><li><a href="czm_sceneModeColumbusView.html" target="_self">czm_sceneModeColumbusView</a></li><li><a href="czm_sceneModeMorphing.html" target="_self">czm_sceneModeMorphing</a></li><li><a href="czm_sunDirectionEC.html" target="_self">czm_sunDirectionEC</a></li><li><a href="czm_sunDirectionWC.html" target="_self">czm_sunDirectionWC</a></li><li><a href="czm_sunPositionColumbusView.html" target="_self">czm_sunPositionColumbusView</a></li><li><a href="czm_sunPositionWC.html" target="_self">czm_sunPositionWC</a></li><li><a href="czm_tangentToEyeSpaceMatrix.html" target="_self">czm_tangentToEyeSpaceMatrix</a></li><li><a href="czm_temeToPseudoFixed.html" target="_self">czm_temeToPseudoFixed</a></li><li><a href="czm_translateRelativeToEye.html" target="_self">czm_translateRelativeToEye</a></li><li><a href="czm_transpose.html" target="_self">czm_transpose</a></li><li><a href="czm_view.html" target="_self">czm_view</a></li><li><a href="czm_view3D.html" target="_self">czm_view3D</a></li><li><a href="czm_viewerPositionWC.html" target="_self">czm_viewerPositionWC</a></li><li><a href="czm_viewport.html" target="_self">czm_viewport</a></li><li><a href="czm_viewportOrthographic.html" target="_self">czm_viewportOrthographic</a></li><li><a href="czm_viewportTransformation.html" target="_self">czm_viewportTransformation</a></li><li><a href="czm_viewProjection.html" target="_self">czm_viewProjection</a></li><li><a href="czm_viewRotation.html" target="_self">czm_viewRotation</a></li><li><a href="czm_viewRotation3D.html" target="_self">czm_viewRotation3D</a></li><li><a href="czm_webMercatorMaxLatitude.html" target="_self">czm_webMercatorMaxLatitude</a></li><li><a href="czm_windowToEyeCoordinates.html" target="_self">czm_windowToEyeCoordinates</a></li><li><a href="czm_XYZToRGB.html" target="_self">czm_XYZToRGB</a></li></div></ul>
    </div>
</div>
<div class="nav navStatic"></div>

<div id="main">
    
    <h1 class="page-title">Context</h1>
    
    

<section>
    
<header>
    <h2>
    Context
    </h2>
    
</header>  

<article>
    <div class="container-overview">
    
    
    
        
<dt>
    <h4 class="name" id="Context"><span class="type-signature"></span>new <a href="#Context" class="permalink" target="_self">Context</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: The browser does not support WebGL.  Visit http://get.webgl.org.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: The browser supports WebGL, but initialization failed.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: canvas is required.
</div>

</li>
        </ul>
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 195</li></ul></dd>
	
    -->
    
	
     
	
	
	
	
	<h5>Source:</h5> 
		<ul class="see-list">
			<li><a href="https://github.com/AnalyticalGraphicsInc/cesium/blob/b25xt.js" target="_blank">xt.js</a></li>
		</ul>
	

	
</dl>

	
	<div class="hr"></div>
</dd>

    
    </div>
    
    
    
    
    
    
    
    
    
    
    
    
        <h3 class="subsection-title">Members</h3>
        
        <dl>
            
<dt>
    <h4 class="name" id="options"><span class="type-signature"><constant> </span><a href="#options" class="permalink" target="_self">options</a><span class="type-signature"> :Object</span></h4>
    
    
</dt>
<dd>
    
    <div class="description">返回用于创建此上下文的只读选项。<code>webgl</code>属性对应于创建WebGL上下文时使用的<a href="http://www.khronos.org/registry/webgl/specs/latest/#5.2">WebGLContextAttributes</a>对象。默认值如下方代码示例所示。

<p>
<code>options.webgl.alpha</code>默认为false，相比WebGL标准默认值true可提升性能。若应用需要通过alpha混合将Cesium合成在其他HTML元素上方，请将<code>options.webgl.alpha</code>设为true。
</p>

<p>
<code>options.webgl.failIfMajorPerformanceCaveat</code>默认为true，这能确保当系统存在重大性能问题（如仅支持软件渲染）时不会成功创建上下文。WebGL标准默认值为false，这对绝大多数Cesium应用都不适用。
</p>

<p>
其余<code>options.webgl</code>属性与<a href="http://www.khronos.org/registry/webgl/specs/latest/#5.2">WebGLContextAttributes</a>的WebGL默认值保持一致。
</p>

<p>
<code>options.allowTextureFilterAnisotropic</code>默认为true，当支持WebGL扩展时会启用各向异性纹理过滤。详见<a href="Context.html#getTextureFilterAnisotropic" target="_self">Context#getTextureFilterAnisotropic</a>。设为false可提升性能，但会降低视觉质量（特别是地平线视图）。
</p></div>
    
        
    
        <h5>Example</h5>
        
    <pre class="code brush: js">{
  webgl : {
    alpha : false,
    depth : true,
    stencil : false,
    antialias : true,
    premultipliedAlpha : true,
    preserveDrawingBuffer : false
    failIfMajorPerformanceCaveat : true
  },
  allowTextureFilterAnisotropic : true
}</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 342</li></ul></dd>
	
    -->
    
	
     
	
	
	
	

	
</dl>

	<div class="hr"></div>
</dd>

        </dl>
    
    
    
        <h3 class="subsection-title">Methods</h3>
        
        <dl>
            
<dt>
    <h4 class="name" id="clear"><span class="type-signature"></span><a href="#clear" class="permalink" target="_self">clear</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">执行指定的清除命令。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>clearCommand</code></td>
            
            
            <td class="type">
            
                        <a href="ClearCommand.html" target="_self">ClearCommand</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
            
            <td class="description last">用于清除的命令。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>passState</code></td>
            
            
            <td class="type">
            
                        <a href="PassState.html" target="_self">PassState</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
            
            <td class="description last">当前渲染通道的状态。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2106</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="ClearCommand.html" target="_self">ClearCommand</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createCubeMap"><span class="type-signature"></span><a href="#createCubeMap" class="permalink" target="_self">createCubeMap</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">DOC_TBA.

options.source 可以是 {ImageData}、{HTMLImageElement}、{HTMLCanvasElement} 或 {HTMLVideoElement}。</p>
    
    
	
	
    
    
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: When options.pixelDatatype is FLOAT, this WebGL implementation must support the OES_texture_float extension.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: options.source requires positiveX, negativeX, positiveY, negativeY, positiveZ, and negativeZ faces.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Each face in options.sources must have the same width and height.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: options requires a source field to create an initialized cube map or width and height fields to create a blank cube map.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width must equal height.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width and height must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width and height must be less than or equal to the maximum cube map size.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid options.pixelFormat.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: options.pixelFormat cannot be DEPTH_COMPONENT or DEPTH_STENCIL.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid options.pixelDatatype.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="CubeMap.html" target="_self">CubeMap</a></span> 
		
		 DOC_TBA.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1647</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2D" target="_self">Context#createTexture2D</a></li>
	
		<li><a href="Context.html#createTexture2DFromFramebuffer" target="_self">Context#createTexture2DFromFramebuffer</a></li>
	
		<li><a href="Context.html#createSampler" target="_self">Context#createSampler</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createFramebuffer"><span class="type-signature"></span><a href="#createFramebuffer" class="permalink" target="_self">createFramebuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建一个带有可选初始颜色、深度和模板附件（attachments）的帧缓冲区（framebuffer）。

帧缓冲区用于实现渲染到纹理（render-to-texture）效果：它们允许我们在第一遍渲染时将场景绘制到纹理上，然后在后续渲染过程中读取这些纹理数据。

（注：根据GIS可视化场景特点，保留"render-to-texture"等专业术语的英文表达，同时采用"帧缓冲区"等计算机图形学标准译法，通过分号拆分为两个技术短句，更符合中文技术文档表述习惯）</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>options</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
            
            <td class="description last">如下例所示的初始帧缓冲附件配置。可用的属性包括<code>colorTextures</code>（颜色纹理）、<code>colorRenderbuffers</code>（颜色渲染缓冲）、<code>depthTexture</code>（深度纹理）、<code>depthRenderbuffer</code>（深度渲染缓冲）、<code>stencilRenderbuffer</code>（模板渲染缓冲）、<code>depthStencilTexture</code>（深度模板纹理）以及<code>depthStencilRenderbuffer</code>（深度模板渲染缓冲）。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both color texture and color renderbuffer attachments.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both a depth texture and depth renderbuffer attachment.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both a depth-stencil texture and depth-stencil renderbuffer attachment.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both a depth and depth-stencil renderbuffer.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both a stencil and depth-stencil renderbuffer.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Cannot have both a depth and stencil renderbuffer.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The color-texture pixel-format must be a color format.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The depth-texture pixel-format must be DEPTH_COMPONENT.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The depth-stencil-texture pixel-format must be DEPTH_STENCIL.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The number of color attachments exceeds the number supported.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="Framebuffer.html" target="_self">Framebuffer</a></span> 
		
		 The created framebuffer.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Create a framebuffer with color and depth texture attachments.
var width = context.getCanvas().clientWidth;
var height = context.getCanvas().clientHeight;
var framebuffer = context.createFramebuffer({
  colorTextures : [context.createTexture2D({
    width : width,
    height : height,
    pixelFormat : PixelFormat.RGBA
  })],
  depthTexture : context.createTexture2D({
    width : width,
    height : height,
    pixelFormat : PixelFormat.DEPTH_COMPONENT,
    pixelDatatype : PixelDatatype.UNSIGNED_SHORT
  })
});</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1804</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2D" target="_self">Context#createTexture2D</a></li>
	
		<li><a href="Context.html#createCubeMap" target="_self">Context#createCubeMap</a></li>
	
		<li><a href="Context.html#createRenderbuffer" target="_self">Context#createRenderbuffer</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createIndexBuffer"><span class="type-signature"></span><a href="#createIndexBuffer" class="permalink" target="_self">createIndexBuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建一个索引缓冲区，该缓冲区包含GPU控制内存中的类型化索引。

<br><br>
索引缓冲区可以附加到顶点数组上，用于选择要渲染的顶点。
<code>Context.draw</code> 可以使用整个索引缓冲区或通过偏移量和计数定义的索引缓冲区子集进行渲染。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>typedArrayOrSizeInBytes</code></td>
            
            
            <td class="type">
            
                        ArrayBufferView
                         | 
                    
                        Number
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">包含要复制到缓冲区的数据的类型化数组，或一个定义缓冲区大小（以字节为单位）的<code>Number</code>。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>usage</code></td>
            
            
            <td class="type">
            
                        <a href="BufferUsage.html" target="_self">BufferUsage</a>
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">指定缓冲区的预期使用模式。在某些GL实现中，这可能会显著影响性能。详见<a href="BufferUsage.html" target="_self">BufferUsage</a>。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>indexDatatype</code></td>
            
            
            <td class="type">
            
                        <a href="IndexDatatype.html" target="_self">IndexDatatype</a>
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">缓冲区中索引的数据类型。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: IndexDatatype.UNSIGNED_INT requires OES_element_index_uint, which is not supported on this system.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The size in bytes must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid <code>usage</code>.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid <code>indexDatatype</code>.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">IndexBuffer</span> 
		
		 The index buffer, ready to be attached to a vertex array.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1. Create a stream index buffer of unsigned shorts that is
// 16 bytes in size.
var buffer = context.createIndexBuffer(16, BufferUsage.STREAM_DRAW,
    IndexDatatype.UNSIGNED_SHORT);

////////////////////////////////////////////////////////////////////////////////

// Example 2. Create a static index buffer containing three unsigned shorts.
var buffer = context.createIndexBuffer(new Uint16Array([0, 1, 2]),
    BufferUsage.STATIC_DRAW, IndexDatatype.UNSIGNED_SHORT)</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1283</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="Context.html#createVertexBuffer" target="_self">Context#createVertexBuffer</a></li>
	
		<li><a href="Context.html#draw" target="_self">Context#draw</a></li>
	
		<li><a href="VertexArray.html" target="_self">VertexArray</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGenBuffer.xml">glGenBuffer</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glBindBuffer.xml">glBindBuffer</a> with <code>ELEMENT_ARRAY_BUFFER</code></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glBufferData.xml">glBufferData</a> with <code>ELEMENT_ARRAY_BUFFER</code></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createPickFramebuffer"><span class="type-signature"></span><a href="#createPickFramebuffer" class="permalink" target="_self">createPickFramebuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2656</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Scene.html#pick" target="_self">Scene#pick</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createPickId"><span class="type-signature"></span><a href="#createPickId" class="permalink" target="_self">createPickId</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建一个与输入对象关联的唯一ID，用于颜色缓冲拾取功能。
该ID具有在当前上下文中唯一的RGBA颜色值。当销毁输入对象时，
必须调用该拾取ID的destroy()方法进行销毁。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>object</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">与拾取ID相关联的对象。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: object is required.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: Out of unique Pick IDs.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Object</span> 
		
		 A PickId object with a <code>color</code> property.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">this._pickId = context.createPickId({
  primitive : this,
  id : this.id
});</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2719</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getObjectByPickColor" target="_self">Context#getObjectByPickColor</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createRenderbuffer"><span class="type-signature"></span><a href="#createRenderbuffer" class="permalink" target="_self">createRenderbuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>options</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
            
            <td class="description last">文档待补充。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid format.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width must be less than or equal to the maximum renderbuffer size.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Height must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Height must be less than or equal to the maximum renderbuffer size.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">createRenderbuffer</span> 
		
		 DOC_TBA.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1825</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createFramebuffer" target="_self">Context#createFramebuffer</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createRenderState"><span class="type-signature"></span><a href="#createRenderState" class="permalink" target="_self">createRenderState</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">验证并查找或创建一个不可变的渲染状态对象，该对象定义了<a href="DrawCommand.html" target="_self">DrawCommand</a>或<a href="ClearCommand.html" target="_self">ClearCommand</a>的管线状态。所有输入状态均为可选参数，未提供的状态将使用如下示例所示的默认值。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>renderState</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">定义渲染状态的状态，如下例所示。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: renderState.lineWidth is out of range.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.frontFace.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.cull.face.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: scissorTest.rectangle.width and scissorTest.rectangle.height must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.depthRange.near can't be greater than renderState.depthRange.far.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.depthRange.near must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.depthRange.far must be less than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.depthTest.func.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.blending.color components must be greater than or equal to zero and less than or equal to one
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.equationRgb.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.equationAlpha.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.functionSourceRgb.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.functionSourceAlpha.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.functionDestinationRgb.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.blending.functionDestinationAlpha.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.frontFunction.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.backFunction.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.frontOperation.fail.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.frontOperation.zFail.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.frontOperation.zPass.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.backOperation.fail.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.backOperation.zFail.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid renderState.stencilTest.backOperation.zPass.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.viewport.width must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.viewport.width must be less than or equal to the maximum viewport width.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.viewport.height must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: renderState.viewport.height must be less than or equal to the maximum viewport height.
</div>

</li>
        </ul>
    
     
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">var defaults = {
    frontFace : WindingOrder.COUNTER_CLOCKWISE,
    cull : {
        enabled : false,
        face : CullFace.BACK
    },
    lineWidth : 1,
    polygonOffset : {
        enabled : false,
        factor : 0,
        units : 0
    },
    scissorTest : {
        enabled : false,
        rectangle : {
            x : 0,
            y : 0,
            width : 0,
            height : 0
        }
    },
    depthRange : {
        near : 0,
        far : 1
    },
    depthTest : {
        enabled : false,
        func : DepthFunction.LESS
     },
    colorMask : {
        red : true,
        green : true,
        blue : true,
        alpha : true
    },
    depthMask : true,
    stencilMask : ~0,
    blending : {
        enabled : false,
        color : {
            red : 0.0,
            green : 0.0,
            blue : 0.0,
            alpha : 0.0
        },
        equationRgb : BlendEquation.ADD,
        equationAlpha : BlendEquation.ADD,
        functionSourceRgb : BlendFunction.ONE,
        functionSourceAlpha : BlendFunction.ONE,
        functionDestinationRgb : BlendFunction.ZERO,
        functionDestinationAlpha : BlendFunction.ZERO
    },
    stencilTest : {
        enabled : false,
        frontFunction : StencilFunction.ALWAYS,
        backFunction : StencilFunction.ALWAYS,
        reference : 0,
        mask : ~0,
        frontOperation : {
            fail : StencilOperation.KEEP,
            zFail : StencilOperation.KEEP,
            zPass : StencilOperation.KEEP
        },
        backOperation : {
            fail : StencilOperation.KEEP,
            zFail : StencilOperation.KEEP,
            zPass : StencilOperation.KEEP
        }
    },
    sampleCoverage : {
        enabled : false,
        value : 1.0,
        invert : false
     },
    dither : true
};

// Same as just context.createRenderState().
var rs = context.createRenderState(defaults);</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1982</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="DrawCommand.html" target="_self">DrawCommand</a></li>
	
		<li><a href="ClearCommand.html" target="_self">ClearCommand</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createSampler"><span class="type-signature"></span><a href="#createSampler" class="permalink" target="_self">createSampler</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid sampler.wrapS.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid sampler.wrapT.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid sampler.minificationFilter.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid sampler.magnificationFilter.
</div>

</li>
        </ul>
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2021</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2D" target="_self">Context#createTexture2D</a></li>
	
		<li><a href="Context.html#createCubeMap" target="_self">Context#createCubeMap</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createShaderProgram"><span class="type-signature"></span><a href="#createShaderProgram" class="permalink" target="_self">createShaderProgram</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">根据给定的顶点着色器和片段着色器的GLSL源代码创建着色器程序。

顶点着色器和片段着色器将分别进行编译，然后链接在一起以创建着色器程序。如果在过程中遇到任何错误，将抛出异常，具体描述如下。

程序的活动uniform和attribute变量将被查询，并可以通过返回的着色器程序进行访问。调用者可以使用可选的<code>attributeLocations</code>参数（如下面第二个示例所示）显式定义顶点属性的索引位置。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>vertexShaderSource</code></td>
            
            
            <td class="type">
            
                        String
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                </td>
            
            
            <td class="description last">顶点着色器的GLSL源代码。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>fragmentShaderSource</code></td>
            
            
            <td class="type">
            
                        String
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                </td>
            
            
            <td class="description last">片段着色器的GLSL源代码。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>attributeLocations</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">一个可选对象，用于将顶点属性名称映射到顶点数组使用的索引。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: Vertex shader failed to compile.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: Fragment shader failed to compile.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: Program failed to link.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="ShaderProgram.html" target="_self">ShaderProgram</a></span> 
		
		 The compiled and linked shader program, ready for use in a draw call.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1. Create a shader program allowing the GL to determine
// attribute indices.
var vs = 'attribute vec4 position; void main() { gl_Position = position; }';
var fs = 'void main() { gl_FragColor = vec4(1.0); }';
var sp = context.createShaderProgram(vs, fs);

////////////////////////////////////////////////////////////////////////////////

// Example 2. Create a shader program with explicit attribute indices.
var vs = 'attribute vec4 position;' +
         'attribute vec3 normal;' +
         'void main() { ... }';
var fs = 'void main() { gl_FragColor = vec4(1.0); }';
var attributes = {
    position : 0,
    normal   : 1
};
sp = context.createShaderProgram(vs, fs, attributes);            *</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1170</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#draw" target="_self">Context#draw</a></li>
	
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="Context.html#getShaderCache" target="_self">Context#getShaderCache</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glCreateShader.xml">glCreateShader</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glShaderSource.xml">glShaderSource</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glCompileShader.xml">glCompileShader</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glCreateProgram.xml">glCreateProgram</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glAttachShader.xml">glAttachShader</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glLinkProgram.xml">glLinkProgram</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetShaderiv.xml">glGetShaderiv</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetActiveUniform.xml">glGetActiveUniform</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetUniformLocation.xml">glGetUniformLocation</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetUniform.xml">glGetUniform</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glBindAttribLocation.xml">glBindAttribLocation</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetActiveAttrib.xml">glGetActiveAttrib</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetAttribLocation.xml">glGetAttribLocation</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createTexture2D"><span class="type-signature"></span><a href="#createTexture2D" class="permalink" target="_self">createTexture2D</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充。

options.source 可以是 {ImageData}、{HTMLImageElement}、{HTMLCanvasElement} 或 {HTMLVideoElement}。</p>
    
    
	
	
    
    
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: When options.pixelFormat is DEPTH_COMPONENT or DEPTH_STENCIL, this WebGL implementation must support WEBGL_depth_texture.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: When options.pixelDatatype is FLOAT, this WebGL implementation must support the OES_texture_float extension.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: options requires a source field to create an initialized texture or width and height fields to create a blank texture.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Width must be less than or equal to the maximum texture size.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Height must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Height must be less than or equal to the maximum texture size.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid options.pixelFormat.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid options.pixelDatatype.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: When options.pixelFormat is DEPTH_COMPONENT, options.pixelDatatype must be UNSIGNED_SHORT or UNSIGNED_INT.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: When options.pixelFormat is DEPTH_STENCIL, options.pixelDatatype must be UNSIGNED_INT_24_8_WEBGL.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: When options.pixelFormat is DEPTH_COMPONENT or DEPTH_STENCIL, source cannot be provided.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="Texture.html" target="_self">Texture</a></span> 
		
		 DOC_TBA.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1431</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2DFromFramebuffer" target="_self">Context#createTexture2DFromFramebuffer</a></li>
	
		<li><a href="Context.html#createCubeMap" target="_self">Context#createCubeMap</a></li>
	
		<li><a href="Context.html#createSampler" target="_self">Context#createSampler</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createTexture2DFromFramebuffer"><span class="type-signature"></span><a href="#createTexture2DFromFramebuffer" class="permalink" target="_self">createTexture2DFromFramebuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建纹理，并将帧缓冲区的子图像复制到其中。当不带参数调用时，纹理的宽度和高度与帧缓冲区相同，并包含其内容。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>pixelFormat</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    PixelFormat.RGB
                
                </td>
            
            
            <td class="description last">纹理的内部像素格式。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>framebufferXOffset</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    0
                
                </td>
            
            
            <td class="description last">帧缓冲区中开始复制的x方向偏移量。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>framebufferYOffset</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    0
                
                </td>
            
            
            <td class="description last">在帧缓冲区中，复制操作起始位置的y方向偏移量。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>width</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    canvas.clientWidth
                
                </td>
            
            
            <td class="description last">纹理的宽度（以纹素为单位）。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>height</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    canvas.clientHeight
                
                </td>
            
            
            <td class="description last">纹理的高度（以纹素为单位）。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid pixelFormat.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: pixelFormat cannot be DEPTH_COMPONENT or DEPTH_STENCIL.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: framebufferXOffset must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: framebufferYOffset must be greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: framebufferXOffset + width must be less than or equal to getCanvas().clientWidth.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: framebufferYOffset + height must be less than or equal to getCanvas().clientHeight.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="Texture.html" target="_self">Texture</a></span> 
		
		 A texture with contents from the framebuffer.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Create a texture with the contents of the framebuffer.
var t = context.createTexture2DFromFramebuffer();</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1556</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2D" target="_self">Context#createTexture2D</a></li>
	
		<li><a href="Context.html#createCubeMap" target="_self">Context#createCubeMap</a></li>
	
		<li><a href="Context.html#createSampler" target="_self">Context#createSampler</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createTextureAtlas"><span class="type-signature"></span><a href="#createTextureAtlas" class="permalink" target="_self">createTextureAtlas</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">使用此上下文创建新的纹理图集。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>options.pixelFormat</code></td>
            
            
            <td class="type">
            
                        <a href="PixelFormat.html" target="_self">PixelFormat</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    PixelFormat.RGBA
                
                </td>
            
            
            <td class="description last">纹理的像素格式。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>options.borderWidthInPixels</code></td>
            
            
            <td class="type">
            
                        Number
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    1
                
                </td>
            
            
            <td class="description last">相邻图像之间的间距量，单位为像素。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>options.initialSize</code></td>
            
            
            <td class="type">
            
                        <a href="Cartesian2.html" target="_self">Cartesian2</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    new Cartesian2(16.0, 16.0)
                
                </td>
            
            
            <td class="description last">纹理的初始边长。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>options.images</code></td>
            
            
            <td class="type">
            
                        Array
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">要添加到图集中的图像数组。等同于调用addImages(images)。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>options.image</code></td>
            
            
            <td class="type">
            
                        Image
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">将单张图片添加到图集中。等同于调用addImage(image)。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="TextureAtlas.html" target="_self">TextureAtlas</a></span> 
		
		 The new texture atlas.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1617</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="TextureAtlas.html" target="_self">TextureAtlas</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createVertexArray"><span class="type-signature"></span><a href="#createVertexArray" class="permalink" target="_self">createVertexArray</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建顶点数组对象，该对象定义了构成顶点的属性集，并可选择性地包含用于渲染顶点选择的索引缓冲区。顶点属性通过对象字面量定义，如下方示例1所示。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>attributes</code></td>
            
            
            <td class="type">
            
                        Array
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">一个可选的属性数组。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>indexBuffer</code></td>
            
            
            <td class="type">
            
                        IndexBuffer
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">一个可选的索引缓冲区。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Attribute must have a <code>vertexBuffer</code>.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Attribute must have a <code>componentsPerAttribute</code>.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Attribute must have a valid <code>componentDatatype</code> or not specify it.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Attribute must have a <code>strideInBytes</code> less than or equal to 255 or not specify it.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Index n is used by more than one attribute.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type"><a href="VertexArray.html" target="_self">VertexArray</a></span> 
		
		 The vertex array, ready for use with drawing.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1. Create a vertex array with vertices made up of three floating point
// values, e.g., a position, from a single vertex buffer.  No index buffer is used.
var positionBuffer = context.createVertexBuffer(12, BufferUsage.STATIC_DRAW);
var attributes = [
    {
        index                  : 0,
        enabled                : true,
        vertexBuffer           : positionBuffer,
        componentsPerAttribute : 3,
        componentDatatype      : ComponentDatatype.FLOAT,
        normalize              : false,
        offsetInBytes          : 0,
        strideInBytes          : 0 // tightly packed
    }
];
var va = context.createVertexArray(attributes);

////////////////////////////////////////////////////////////////////////////////

// Example 2. Create a vertex array with vertices from two different vertex buffers.
// Each vertex has a three-component position and three-component normal.
var positionBuffer = context.createVertexBuffer(12, BufferUsage.STATIC_DRAW);
var normalBuffer = context.createVertexBuffer(12, BufferUsage.STATIC_DRAW);
var attributes = [
    {
        index                  : 0,
        vertexBuffer           : positionBuffer,
        componentsPerAttribute : 3,
        componentDatatype      : ComponentDatatype.FLOAT
    },
    {
        index                  : 1,
        vertexBuffer           : normalBuffer,
        componentsPerAttribute : 3,
        componentDatatype      : ComponentDatatype.FLOAT
    }
];
var va = context.createVertexArray(attributes);

////////////////////////////////////////////////////////////////////////////////

// Example 3. Creates the same vertex layout as Example 2 using a single
// vertex buffer, instead of two.
var buffer = context.createVertexBuffer(24, BufferUsage.STATIC_DRAW);
var attributes = [
    {
        vertexBuffer           : buffer,
        componentsPerAttribute : 3,
        componentDatatype      : ComponentDatatype.FLOAT,
        offsetInBytes          : 0,
        strideInBytes          : 24
    },
    {
        vertexBuffer           : buffer,
        componentsPerAttribute : 3,
        componentDatatype      : ComponentDatatype.FLOAT,
        normalize              : true,
        offsetInBytes          : 12,
        strideInBytes          : 24
    }
];
var va = context.createVertexArray(attributes);</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1401</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createVertexArrayFromGeometry" target="_self">Context#createVertexArrayFromGeometry</a></li>
	
		<li><a href="Context.html#createVertexBuffer" target="_self">Context#createVertexBuffer</a></li>
	
		<li><a href="Context.html#createIndexBuffer" target="_self">Context#createIndexBuffer</a></li>
	
		<li><a href="Context.html#draw" target="_self">Context#draw</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createVertexArrayFromGeometry"><span class="type-signature"></span><a href="#createVertexArrayFromGeometry" class="permalink" target="_self">createVertexArrayFromGeometry</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">从几何体创建顶点数组。几何体包含系统内存中的顶点属性和可选的索引数据，而顶点数组则包含WebGL内存中的顶点缓冲区和可选的索引缓冲区，用于渲染。
<br><br>
<code>geometry</code>参数应采用标准布局，类似于<a href="BoxGeometry.html" target="_self">BoxGeometry</a>返回的几何体。
<br><br>
<code>creationArguments</code>可包含以下四个属性：</p><ul>
  <li><code>geometry</code>:  The source geometry containing data used to create the vertex array.</li>
  <li><code>attributeLocations</code>:  An object that maps geometry attribute names to vertex shader attribute locations.</li>
  <li><code>bufferUsage</code>:  The expected usage pattern of the vertex array's buffers.  On some WebGL implementations, this can significantly affect performance.  See <a href="BufferUsage.html" target="_self">BufferUsage</a>.  Default: <code>BufferUsage.DYNAMIC_DRAW</code>.</li>
  <li><code>vertexLayout</code>:  Determines if all attributes are interleaved in a single vertex buffer or if each attribute is stored in a separate vertex buffer.  Default: <code>VertexLayout.SEPARATE</code>.</li>
</ul>
<br>
If <code>creationArguments</code> is not specified or the <code>geometry</code> contains no data, the returned vertex array is empty.
    <p></p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		<th>Default</th>
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>creationArguments</code></td>
            
            
            <td class="type">
            
                        Object
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
                <td class="default">
                
                    undefined
                
                </td>
            
            
            <td class="description last">一个对象，用于定义创建顶点数组所需的几何结构、属性索引、缓冲区用途以及顶点布局。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="RuntimeError.html" target="_self">RuntimeError</a></span> 
		
	: Each attribute list must have the same number of vertices.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The geometry must have zero or one index lists.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Index n is used by more than one attribute.
</div>

</li>
        </ul>
    
     
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1. Creates a vertex array for rendering a box.  The default dynamic draw
// usage is used for the created vertex and index buffer.  The attributes are not
// interleaved by default.
var geometry = new BoxGeometry();
var va = context.createVertexArrayFromGeometry({
    geometry           : geometry,
    attributeLocations : GeometryPipeline.createAttributeLocations(geometry),
});

////////////////////////////////////////////////////////////////////////////////

// Example 2. Creates a vertex array with interleaved attributes in a
// single vertex buffer.  The vertex and index buffer have static draw usage.
var va = context.createVertexArrayFromGeometry({
    geometry           : geometry,
    attributeLocations : GeometryPipeline.createAttributeLocations(geometry),
    bufferUsage        : BufferUsage.STATIC_DRAW,
    vertexLayout       : VertexLayout.INTERLEAVED
});

////////////////////////////////////////////////////////////////////////////////

// Example 3.  When the caller destroys the vertex array, it also destroys the
// attached vertex buffer(s) and index buffer.
va = va.destroy();</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2557</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="Context.html#createVertexBuffer" target="_self">Context#createVertexBuffer</a></li>
	
		<li><a href="Context.html#createIndexBuffer" target="_self">Context#createIndexBuffer</a></li>
	
		<li><a href="GeometryPipeline.html#createAttributeLocations" target="_self">GeometryPipeline.createAttributeLocations</a></li>
	
		<li><a href="ShaderProgram.html" target="_self">ShaderProgram</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="createVertexBuffer"><span class="type-signature"></span><a href="#createVertexBuffer" class="permalink" target="_self">createVertexBuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">创建一个顶点缓冲区，其中包含GPU控制内存中的无类型顶点数据。

<br><br>
顶点数组通过解释一个或多个顶点缓冲区中的原始数据，来定义顶点的实际组成，例如位置、法线、纹理坐标等。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>typedArrayOrSizeInBytes</code></td>
            
            
            <td class="type">
            
                        ArrayBufferView
                         | 
                    
                        Number
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">一个包含要复制到缓冲区数据的类型化数组，或者一个<code>Number</code>类型值（用于定义缓冲区大小的字节数）。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>usage</code></td>
            
            
            <td class="type">
            
                        <a href="BufferUsage.html" target="_self">BufferUsage</a>
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">指定缓冲区的预期使用模式。在某些GL实现中，这可能会显著影响性能。详见<a href="BufferUsage.html" target="_self">BufferUsage</a>。</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: The size in bytes must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Invalid <code>usage</code>.
</div>

</li>
        </ul>
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">VertexBuffer</span> 
		
		 The vertex buffer, ready to be attached to a vertex array.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1. Create a dynamic vertex buffer 16 bytes in size.
var buffer = context.createVertexBuffer(16, BufferUsage.DYNAMIC_DRAW);

////////////////////////////////////////////////////////////////////////////////

// Example 2. Create a dynamic vertex buffer from three floating-point values.
// The data copied to the vertex buffer is considered raw bytes until it is
// interpreted as vertices using a vertex array.
var positionBuffer = context.createVertexBuffer(new Float32Array([0, 0, 0]),
    BufferUsage.STATIC_DRAW);</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1239</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="Context.html#createIndexBuffer" target="_self">Context#createIndexBuffer</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGenBuffer.xml">glGenBuffer</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glBindBuffer.xml">glBindBuffer</a> with <code>ARRAY_BUFFER</code></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glBufferData.xml">glBufferData</a> with <code>ARRAY_BUFFER</code></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="draw"><span class="type-signature"></span><a href="#draw" class="permalink" target="_self">draw</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">执行指定的绘制命令。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		<th>Argument</th>
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>drawCommand</code></td>
            
            
            <td class="type">
            
                        <a href="DrawCommand.html" target="_self">DrawCommand</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    
                
                </td>
            
            
            
            
            <td class="description last">用于绘制的命令。</td>
        </tr>
	
	
	
        <tr>
            
                <td class="name"><code>passState</code></td>
            
            
            <td class="type">
            
                        <a href="PassState.html" target="_self">PassState</a>
                        
                    
            </td>
            
            
                <td class="attributes">
                
                    <optional><br>
                
                    
                
                </td>
            
            
            
            
            <td class="description last">当前渲染通道的状态</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand is required.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand.primitiveType is required and must be valid.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand.shaderProgram is required.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand.vertexArray is required.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand.offset must be omitted or greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: drawCommand.count must be omitted or greater than or equal to zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Program validation failed.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: Framebuffer is not complete.
</div>

</li>
        </ul>
    
     
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">// Example 1.  Draw a single triangle specifying only required arguments
context.draw({
    primitiveType : PrimitiveType.TRIANGLES,
    shaderProgram : sp,
    vertexArray   : va,
});

////////////////////////////////////////////////////////////////////////////////

// Example 2.  Draw a single triangle specifying every argument
context.draw({
    primitiveType : PrimitiveType.TRIANGLES,
    offset        : 0,
    count         : 3,
    framebuffer   : fb,
    shaderProgram : sp,
    vertexArray   : va,
    renderState   : rs
});</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 2292</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createShaderProgram" target="_self">Context#createShaderProgram</a></li>
	
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="Context.html#createFramebuffer" target="_self">Context#createFramebuffer</a></li>
	
		<li><a href="Context.html#createRenderState" target="_self">Context#createRenderState</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getAlphaBits"><span class="type-signature"></span><a href="#getAlphaBits" class="permalink" target="_self">getAlphaBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认帧缓冲区的颜色缓冲区中每个颜色分量的alpha位数。最小值为8位。

<br><br>
alpha通道用于GL目标alpha操作，并被HTML合成器用来将颜色缓冲区与页面其他部分进行合成。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of alpha bits per component in the color buffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 499</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>ALPHA_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getAntialias"><span class="type-signature"></span><a href="#getAntialias" class="permalink" target="_self">getAntialias</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果WebGL上下文支持抗锯齿，则返回<code>true</code>。默认情况下会请求抗锯齿功能，但并非所有系统都支持该功能。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if antialiasing is supported.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 773</li></ul></dd>
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getBlueBits"><span class="type-signature"></span><a href="#getBlueBits" class="permalink" target="_self">getBlueBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认帧缓冲区的颜色缓冲区中每个颜色分量的蓝色位数。最小值为八位。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of blue bits per component in the color buffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 484</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>BLUE_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getCanvas"><span class="type-signature"></span><a href="#getCanvas" class="permalink" target="_self">getCanvas</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回与此上下文关联的画布。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">HTMLCanvasElement</span> 
		
		 The canvas assoicated with this context.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 377</li></ul></dd>
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDefaultCubeMap"><span class="type-signature"></span><a href="#getDefaultCubeMap" class="permalink" target="_self">getDefaultCubeMap</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回一个立方体贴图，其中每个面都是初始化为[255, 255, 255, 255]的1x1 RGBA纹理。在其他立方体贴图下载完成前，可用作占位立方体贴图。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1060</li></ul></dd>
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDefaultTexture"><span class="type-signature"></span><a href="#getDefaultTexture" class="permalink" target="_self">getDefaultTexture</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回一个初始化为[255, 255, 255, 255]的1x1 RGBA纹理。该纹理可用作其他纹理下载完成前的占位纹理。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1037</li></ul></dd>
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDepthBits"><span class="type-signature"></span><a href="#getDepthBits" class="permalink" target="_self">getDepthBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认绑定帧缓冲区中每个像素的深度位数。最小为16位；大多数实现将提供24位。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of depth bits per pixel in the default bound framebuffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 512</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>DEPTH_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDepthTexture"><span class="type-signature"></span><a href="#getDepthTexture" class="permalink" target="_self">getDepthTexture</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持WEBGL_depth_texture扩展则返回<code>true</code>。该扩展提供了深度纹理访问功能，例如可将深度纹理附加到帧缓冲区用于阴影映射。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if WEBGL_depth_texture is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 818</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/WEBGL_depth_texture/">WEBGL_depth_texture</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDrawBuffers"><span class="type-signature"></span><a href="#getDrawBuffers" class="permalink" target="_self">getDrawBuffers</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持WEBGL_draw_buffers扩展则返回<code>true</code>。该扩展提供了对多渲染目标的支持，帧缓冲对象可以拥有多个颜色附件，且GLSL片段着色器能够写入内置输出数组<code>gl_FragData</code>。使用此特性的着色器需要通过<code>#extension GL_EXT_draw_buffers : enable</code>显式启用该扩展。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if WEBGL_draw_buffers is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 904</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/WEBGL_draw_buffers/">WEBGL_draw_buffers</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDrawingBufferHeight"><span class="type-signature"></span><a href="#getDrawingBufferHeight" class="permalink" target="_self">getDrawingBufferHeight</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回底层GL上下文的drawingBufferWidth属性。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The value in the drawingBufferWidth property of the underlying GL context.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1092</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="https://www.khronos.org/registry/webgl/specs/1.0/#DOM-WebGLRenderingContext-drawingBufferWidth">drawingBufferWidth</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getDrawingBufferWidth"><span class="type-signature"></span><a href="#getDrawingBufferWidth" class="permalink" target="_self">getDrawingBufferWidth</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回底层GL上下文的drawingBufferHeight属性。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The value in the drawingBufferHeight property of the underlying GL context.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1105</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="https://www.khronos.org/registry/webgl/specs/1.0/#DOM-WebGLRenderingContext-drawingBufferHeight">drawingBufferHeight</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getElementIndexUint"><span class="type-signature"></span><a href="#getElementIndexUint" class="permalink" target="_self">getElementIndexUint</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持OES_element_index_uint扩展则返回<code>true</code>。该扩展允许使用无符号整型索引，通过消除无符号短整型索引引起的批次中断，可以提升渲染性能。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if OES_element_index_uint is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 804</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/OES_element_index_uint/">OES_element_index_uint</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getFloatingPointTexture"><span class="type-signature"></span><a href="#getFloatingPointTexture" class="permalink" target="_self">getFloatingPointTexture</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持OES_texture_float扩展则返回<code>true</code>。该扩展提供了对浮点纹理的访问能力，例如可将浮点纹理附加到帧缓冲区以实现高动态范围效果。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if OES_texture_float is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 832</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/gles/extensions/OES/OES_texture_float.txt">OES_texture_float</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getFragmentDepth"><span class="type-signature"></span><a href="#getFragmentDepth" class="permalink" target="_self">getFragmentDepth</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持EXT_frag_depth扩展则返回<code>true</code>。该扩展提供了从GLSL片段着色器访问内置输出变量<code>gl_FragDepthEXT</code>的能力。使用这些函数的着色器仍需通过<code>#extension GL_EXT_frag_depth : enable</code>显式启用该扩展。</p><code><code>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if EXT_frag_depth is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 887</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/EXT_frag_depth/">EXT_frag_depth</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</code></code></dd><code><code>

        
            
<dt>
    <h4 class="name" id="getGreenBits"><span class="type-signature"></span><a href="#getGreenBits" class="permalink" target="_self">getGreenBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认帧缓冲颜色缓冲区中每个分量的绿色位数。最小值为八位。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of green bits per component in the color buffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 472</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>GREEN_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getId"><span class="type-signature"></span><a href="#getId" class="permalink" target="_self">getId</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此上下文的唯一ID。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">String</span> 
		
		 A unique ID for this context.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getLogShaderCompilation"><span class="type-signature"></span><a href="#getLogShaderCompilation" class="permalink" target="_self">getLogShaderCompilation</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 1014</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setLogShaderCompilation" target="_self">Context#setLogShaderCompilation</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumAliasedLineWidth"><span class="type-signature"></span><a href="#getMaximumAliasedLineWidth" class="permalink" target="_self">getMaximumAliasedLineWidth</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现支持的最大抗锯齿线宽（以像素为单位）。该值至少为1。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum aliased line in pixels.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 705</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMinimumAliasedLineWidth" target="_self">Context#getMinimumAliasedLineWidth</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>ALIASED_LINE_WIDTH_RANGE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumAliasedPointSize"><span class="type-signature"></span><a href="#getMaximumAliasedPointSize" class="permalink" target="_self">getMaximumAliasedPointSize</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现支持的最大抗锯齿点尺寸（以像素为单位）。该值至少为1。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum aliased point size in pixels.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 733</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMinimumAliasedPointSize" target="_self">Context#getMinimumAliasedPointSize</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>ALIASED_POINT_SIZE_RANGE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumColorAttachments"><span class="type-signature"></span><a href="#getMaximumColorAttachments" class="permalink" target="_self">getMaximumColorAttachments</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回支持的最大颜色附件数量。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of color attachments supported.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 926</li></ul></dd>
	
    -->
    
	
     
	
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumCombinedTextureImageUnits"><span class="type-signature"></span><a href="#getMaximumCombinedTextureImageUnits" class="permalink" target="_self">getMaximumCombinedTextureImageUnits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回该WebGL实现中顶点着色器和片段着色器可使用的最大纹理单元数量。最低支持数为八个。如果两个着色器访问同一个纹理单元，则会计为两个纹理单元的使用量。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum supported texture image units.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 541</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumTextureImageUnits" target="_self">Context#getMaximumTextureImageUnits</a></li>
	
		<li><a href="Context.html#getMaximumVertexTextureImageUnits" target="_self">Context#getMaximumVertexTextureImageUnits</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_COMBINED_TEXTURE_IMAGE_UNITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumCubeMapSize"><span class="type-signature"></span><a href="#getMaximumCubeMapSize" class="permalink" target="_self">getMaximumCubeMapSize</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现所支持的大致最大立方体贴图宽度和高度。
最小值为16，但大多数桌面和笔记本电脑的实现将支持更大的尺寸，如8,192。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The approximate maximum cube mape width and height.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 557</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createCubeMap" target="_self">Context#createCubeMap</a></li>
	
		<li><a href="Context.html#getMaximumTextureSize" target="_self">Context#getMaximumTextureSize</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_CUBE_MAP_TEXTURE_SIZE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumDrawBuffers"><span class="type-signature"></span><a href="#getMaximumDrawBuffers" class="permalink" target="_self">getMaximumDrawBuffers</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回片段着色器中可同时写入的最大输出数量。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of draw buffers supported.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 915</li></ul></dd>
	
    -->
    
	
     
	
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumFragmentUniformVectors"><span class="type-signature"></span><a href="#getMaximumFragmentUniformVectors" class="permalink" target="_self">getMaximumFragmentUniformVectors</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现中片段着色器可使用的<code>vec4</code>、<code>ivec4</code>和<code>bvec4</code>类型uniform变量的最大数量。最小支持值为16。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of <code>vec4</code>, <code>ivec4</code>, and <code>bvec4</code> uniforms that can be used by a fragment shader.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 572</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumVertexUniformVectors" target="_self">Context#getMaximumVertexUniformVectors</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_FRAGMENT_UNIFORM_VECTORS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumRenderbufferSize"><span class="type-signature"></span><a href="#getMaximumRenderbufferSize" class="permalink" target="_self">getMaximumRenderbufferSize</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现支持的最大渲染缓冲区宽度和高度。
最小值为16，但大多数桌面和笔记本电脑实现将支持更大的尺寸，例如8,192。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum renderbuffer width and height.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 602</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createRenderbuffer" target="_self">Context#createRenderbuffer</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_RENDERBUFFER_SIZE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumTextureFilterAnisotropy"><span class="type-signature"></span><a href="#getMaximumTextureFilterAnisotropy" class="permalink" target="_self">getMaximumTextureFilterAnisotropy</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 856</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getTextureFilterAnisotropic" target="_self">Context#getTextureFilterAnisotropic</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumTextureImageUnits"><span class="type-signature"></span><a href="#getMaximumTextureImageUnits" class="permalink" target="_self">getMaximumTextureImageUnits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现中片段着色器可使用的最大纹理单元数量，最低支持八个。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of texture units that can be used from the fragment shader.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 587</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumCombinedTextureImageUnits" target="_self">Context#getMaximumCombinedTextureImageUnits</a></li>
	
		<li><a href="Context.html#getMaximumVertexTextureImageUnits" target="_self">Context#getMaximumVertexTextureImageUnits</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_TEXTURE_IMAGE_UNITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumTextureSize"><span class="type-signature"></span><a href="#getMaximumTextureSize" class="permalink" target="_self">getMaximumTextureSize</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现所支持的大致最大纹理宽度和高度。
最小值为64，但大多数桌面和笔记本电脑的实现将支持更大的尺寸，例如8,192。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The approximate maximum texture width and height.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 618</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createTexture2D" target="_self">Context#createTexture2D</a></li>
	
		<li><a href="Context.html#getMaximumCubeMapSize" target="_self">Context#getMaximumCubeMapSize</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_TEXTURE_SIZE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumVaryingVectors"><span class="type-signature"></span><a href="#getMaximumVaryingVectors" class="permalink" target="_self">getMaximumVaryingVectors</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现所支持的最大<code>vec4</code> varying变量数量。
最低支持数量为八个。矩阵和数组会按多个<code>vec4</code>进行计数。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 Returns the maximum number of <code>vec4</code> varying variables.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 632</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VARYING_VECTORS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumVertexAttributes"><span class="type-signature"></span><a href="#getMaximumVertexAttributes" class="permalink" target="_self">getMaximumVertexAttributes</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现所支持的最大<code>vec4</code>顶点属性数量。最低支持数量为八个。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of <code>vec4</code> vertex attributes.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 646</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createVertexArray" target="_self">Context#createVertexArray</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VERTEX_ATTRIBS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumVertexTextureImageUnits"><span class="type-signature"></span><a href="#getMaximumVertexTextureImageUnits" class="permalink" target="_self">getMaximumVertexTextureImageUnits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现下顶点着色器可使用的最大纹理单元数量。
最小值为零，表示该GL实现不支持顶点纹理拾取功能。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of texture units that can be used from the vertex shader.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 662</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumCombinedTextureImageUnits" target="_self">Context#getMaximumCombinedTextureImageUnits</a></li>
	
		<li><a href="Context.html#getMaximumTextureImageUnits" target="_self">Context#getMaximumTextureImageUnits</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VERTEX_TEXTURE_IMAGE_UNITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumVertexUniformVectors"><span class="type-signature"></span><a href="#getMaximumVertexUniformVectors" class="permalink" target="_self">getMaximumVertexUniformVectors</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回当前WebGL实现中顶点着色器可使用的<code>vec4</code>、<code>ivec4</code>和<code>bvec4</code>类型uniform变量的最大数量，最小值为16。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum number of <code>vec4</code>, <code>ivec4</code>, and <code>bvec4</code> uniforms that can be used by a vertex shader.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 677</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumFragmentUniformVectors" target="_self">Context#getMaximumFragmentUniformVectors</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VERTEX_UNIFORM_VECTORS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumViewportHeight"><span class="type-signature"></span><a href="#getMaximumViewportHeight" class="permalink" target="_self">getMaximumViewportHeight</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回视口支持的最大高度。该值至少与关联画布的可见高度相同。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum supported height of the viewport.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 761</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumViewportHeight" target="_self">Context#getMaximumViewportHeight</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VIEWPORT_DIMS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMaximumViewportWidth"><span class="type-signature"></span><a href="#getMaximumViewportWidth" class="permalink" target="_self">getMaximumViewportWidth</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回视口支持的最大宽度。该值至少与关联画布的可见宽度相同。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The maximum supported width of the viewport.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 747</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumViewportHeight" target="_self">Context#getMaximumViewportHeight</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>MAX_VIEWPORT_DIMS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMinimumAliasedLineWidth"><span class="type-signature"></span><a href="#getMinimumAliasedLineWidth" class="permalink" target="_self">getMinimumAliasedLineWidth</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现支持的最小抗锯齿线宽（以像素为单位）。该值最大不超过1。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The minimum aliased line in pixels.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 691</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumAliasedLineWidth" target="_self">Context#getMaximumAliasedLineWidth</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>ALIASED_LINE_WIDTH_RANGE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getMinimumAliasedPointSize"><span class="type-signature"></span><a href="#getMinimumAliasedPointSize" class="permalink" target="_self">getMinimumAliasedPointSize</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回此WebGL实现支持的最小抗锯齿点大小（以像素为单位）。该值最大不超过1。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The minimum aliased point size in pixels.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 719</li></ul></dd>
	
    -->
    
	
     
	
	
	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getMaximumAliasedPointSize" target="_self">Context#getMaximumAliasedPointSize</a></li>
	
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>ALIASED_POINT_SIZE_RANGE</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getObjectByPickColor"><span class="type-signature"></span><a href="#getObjectByPickColor" class="permalink" target="_self">getObjectByPickColor</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">获取与拾取颜色关联的对象。</p>
    
    
	
	
    
    
    
        <h5>Parameters:</h5>
        

<table class="params">
    <thead>
	<tr>
		
		<th>Name</th>
		
		
		<th>Type</th>
		
		
		
		
		
		<th class="last">Description</th>
	</tr>
	</thead>
	
	<tbody>
	
	
        <tr>
            
                <td class="name"><code>The</code></td>
            
            
            <td class="type">
            
                        <a href="Color.html" target="_self">Color</a>
                        
                    
            </td>
            
            
            
            
            
            <td class="description last">拾取颜色</td>
        </tr>
	
	
	</tbody>
</table>
    
    
    
    
    
    <h5>Throws:</h5>
    
            
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: pickColor is required.
</div>


        
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Object</span> 
		
		 The object associated with the pick color, or undefined if no object is associated with that color.
</div>

         
    
    
        <h5>Example</h5>
        
    <pre class="code brush: js">var object = context.getObjectByPickColor(pickColor);</pre>

    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createPickId" target="_self">Context#createPickId</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getRedBits"><span class="type-signature"></span><a href="#getRedBits" class="permalink" target="_self">getRedBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认帧缓冲颜色缓冲区中每个分量的红色位数。最小值为八位。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of red bits per component in the color buffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 460</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>RED_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getRenderer"><span class="type-signature"></span><a href="#getRenderer" class="permalink" target="_self">getRenderer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回渲染器/配置/硬件平台的名称。例如，可能是显卡型号（如'GeForce 8800 GTS/PCI/SSE2'），或是与浏览器相关的GL实现名称（如'Mozilla'或'ANGLE'）。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">String</span> 
		
		 The name of the renderer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 448</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetString.xml">glGetString</a> with <code>RENDERER</code>.</li>
	
		<li><a href="http://code.google.com/p/angleproject/">ANGLE</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getShaderCache"><span class="type-signature"></span><a href="#getShaderCache" class="permalink" target="_self">getShaderCache</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 388</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#createShaderProgram" target="_self">Context#createShaderProgram</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getShadingLanguageVersion"><span class="type-signature"></span><a href="#getShadingLanguageVersion" class="permalink" target="_self">getShadingLanguageVersion</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回着色语言的版本或发布号，格式为：WebGL GLSL ES <版本号> <供应商特定信息>。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">String</span> 
		
		 The version or release number for the shading language.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 420</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetString.xml">glGetString</a> with <code>SHADING_LANGUAGE_VERSION</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getStandardDerivatives"><span class="type-signature"></span><a href="#getStandardDerivatives" class="permalink" target="_self">getStandardDerivatives</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持OES_standard_derivatives扩展则返回<code>true</code>。该扩展提供了从GLSL访问<code>dFdx</code>、<code>dFdy</code>和<code>fwidth</code>函数的能力。使用这些函数的着色器仍需通过<code>#extension GL_OES_standard_derivatives : enable</code>显式启用该扩展。</p><code><code>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if OES_standard_derivatives is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 789</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/gles/extensions/OES/OES_standard_derivatives.txt">OES_standard_derivatives</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</code></code></dd><code><code>

        
            
<dt>
    <h4 class="name" id="getStencilBits"><span class="type-signature"></span><a href="#getStencilBits" class="permalink" target="_self">getStencilBits</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回默认绑定帧缓冲区中每个像素的模板缓冲位数。最小为八位。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Number</span> 
		
		 The number of stencil bits per pixel in the default bound framebuffer.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 524</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGet.xml">glGet</a> with <code>STENCIL_BITS</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getTextureFilterAnisotropic"><span class="type-signature"></span><a href="#getTextureFilterAnisotropic" class="permalink" target="_self">getTextureFilterAnisotropic</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if EXT_texture_filter_anisotropic is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 845</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/EXT_texture_filter_anisotropic/">EXT_texture_filter_anisotropic</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getThrowOnWebGLError"><span class="type-signature"></span><a href="#getThrowOnWebGLError" class="permalink" target="_self">getThrowOnWebGLError</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 987</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setThrowOnWebGLError" target="_self">Context#setThrowOnWebGLError</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getUniformState"><span class="type-signature"></span><a href="#getUniformState" class="permalink" target="_self">getUniformState</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 396</li></ul></dd>
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getValidateFramebuffer"><span class="type-signature"></span><a href="#getValidateFramebuffer" class="permalink" target="_self">getValidateFramebuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 937</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setValidateFramebuffer" target="_self">Context#setValidateFramebuffer</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getValidateShaderProgram"><span class="type-signature"></span><a href="#getValidateShaderProgram" class="permalink" target="_self">getValidateShaderProgram</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 962</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setValidateShaderProgram" target="_self">Context#setValidateShaderProgram</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getVendor"><span class="type-signature"></span><a href="#getVendor" class="permalink" target="_self">getVendor</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回负责WebGL实现的公司。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">String</span> 
		
		 The company responsible for the WebGL implementation.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
	<!--
	
	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 432</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetString.xml">glGetString</a> with <code>VENDOR</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getVersion"><span class="type-signature"></span><a href="#getVersion" class="permalink" target="_self">getVersion</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">返回WebGL版本或发行号，格式为&lt;WebGL&gt;&lt;空格&gt;&lt;版本号&gt;&lt;空格&gt;&lt;厂商特定信息&gt;。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">String</span> 
		
		 The WebGL version or release number.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 408</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/opengles/sdk/2.0/docs/man/glGetString.xml">glGetString</a> with <code>VERSION</code>.</li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="getVertexArrayObject"><span class="type-signature"></span><a href="#getVertexArrayObject" class="permalink" target="_self">getVertexArrayObject</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">如果支持OES_vertex_array_object扩展则返回<code>true</code>。该扩展能通过减少切换顶点数组的开销来提升性能。启用后，<a href="VertexArray.html" target="_self">VertexArray</a>会自动使用此扩展功能。</p>
    
    
	
	
    
    
    
    
    
    
    
    
    
    <h5>Returns:</h5>
    
            
<div class="param-desc">
	
	
		<span class="param-type">Boolean</span> 
		
		 <code>true</code> if OES_vertex_array_object is supported; otherwise, <code>false</code>.
</div>

         
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
	<dd class="tag-source"><ul class="dummy"><li>Context.js, line 871</li></ul></dd>
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="http://www.khronos.org/registry/webgl/extensions/OES_vertex_array_object/">OES_vertex_array_object</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="readPixels"><span class="type-signature"></span><a href="#readPixels" class="permalink" target="_self">readPixels</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    <h5>Throws:</h5>
    <ul>
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: readState.width must be greater than zero.
</div>

</li>
        
            <li>
<div class="param-desc">
    
		
		<span class="param-type"><a href="DeveloperError.html" target="_self">DeveloperError</a></span> 
		
	: readState.height must be greater than zero.
</div>

</li>
        </ul>
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="setLogShaderCompilation"><span class="type-signature"></span><a href="#setLogShaderCompilation" class="permalink" target="_self">setLogShaderCompilation</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#getLogShaderCompilation" target="_self">Context#getLogShaderCompilation</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="setThrowOnWebGLError"><span class="type-signature"></span><a href="#setThrowOnWebGLError" class="permalink" target="_self">setThrowOnWebGLError</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
		<h5>Performance:</h5>
		<p class="description">文档待补充：慢。</p>
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setValidateFramebuffer" target="_self">Context#setValidateFramebuffer</a></li>
	
		<li><a href="Context.html#setValidateShaderProgram" target="_self">Context#setValidateShaderProgram</a></li>
	
		<li><a href="Context.html#getThrowOnWebGLError" target="_self">Context#getThrowOnWebGLError</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="setValidateFramebuffer"><span class="type-signature"></span><a href="#setValidateFramebuffer" class="permalink" target="_self">setValidateFramebuffer</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
		<h5>Performance:</h5>
		<p class="description">文档待补充：速度较慢。</p>
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setValidateShaderProgram" target="_self">Context#setValidateShaderProgram</a></li>
	
		<li><a href="Context.html#getValidateFramebuffer" target="_self">Context#getValidateFramebuffer</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

        
            
<dt>
    <h4 class="name" id="setValidateShaderProgram"><span class="type-signature"></span><a href="#setValidateShaderProgram" class="permalink" target="_self">setValidateShaderProgram</a></h4>
    
    
</dt>
<dd>
    
    
    <p class="description">文档待补充</p>
    
    
	
		<h5>Performance:</h5>
		<p class="description">文档待补充：速度较慢。</p>
	
	
    
    
    
    
    
    
    
    
     
    
    
	
	
<dl class="details">
    
        
	
	
	
	
	
	
	
	
	
	
	
	
	
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	<dt class="tag-source">Source:</dt>
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	<h5>See:</h5>
	<ul class="see-list">
		<li><a href="Context.html#setValidateFramebuffer" target="_self">Context#setValidateFramebuffer</a></li>
	
		<li><a href="Context.html#getValidateShaderProgram" target="_self">Context#getValidateShaderProgram</a></li>
	</ul>
	
	
	

	
</dl>

	
	<div class="hr"></div>
</dd>

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